Withanolides from Vassobia lorentzii

Eight new withanolides were isolated from the aerial parts of Vassobia lorentzii and characterized by spectroscopic methods and with the aid of molecular modeling. The compounds were identified as (17S,20R,22R)-5beta,6beta:18,20-diepoxy-18-hydro xy-1-oxowitha-2,5, 24-trienolide (1); (17S,20R,22R)-18,20-epoxy-4beta, 18-dihydroxy-1-oxowitha-2,5,24-trienolide (2); (17S,18R,20R, 22R)-4beta-hydroxy-18,20-epoxy-18-methoxy-1-oxowitha-2,5, 24-trienolide (3); (17S,18S,20R,22R)-4beta-hydroxy-18, 20-epoxy-18-methoxy-1-oxowitha-2,5,24-trienolide (4); (17S,20R, 22R)-4beta-hydroxy-18,20-epoxy-1,18-dioxowitha-2,5,24-tri enolide (5); (17S,18R,20R,22R)-18,20-epoxy-18-methoxy-1,4-dioxowitha++ +-2,5, 24-trienolide (6); (17S,18S,20R,22R)-18,20-epoxy-18-methoxy-1, 4-dioxowitha-2,5,24-trienolide (7); and (17S,20R,22R)-5beta, 6beta-epoxy-4beta,18,20-trihydroxy-1-oxowitha-2,24-die nolide (8). Compounds 1 and 2 were obtained as epimeric mixtures at C-18.     

Spiranoid withanolides from Jaborosa odonelliana

Six new spiranoid withanolides, (20R,22R,23S)-5alpha-chloro-6beta,12beta,17beta,22-tetrahydroxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (2), (20R,22R,23S)-5beta,6beta-epoxy-12beta,17beta,22-trihydroxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (3), (20R,22R,23S)-5beta,6beta-epoxy-4beta,12beta,17beta,22-tetrahydroxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (4), (20R,22R,23S)-5alpha,6beta,12beta,17beta,22-pentahydroxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (5), (20R,22R,23S)-6beta,12beta,17beta,22-tetrahydroxy-5alpha-methoxy-1-oxo-12,23-cycloergosta-2,24-dien-26,23-olide (6), and (20R,22R,23S)-6beta,12beta,17beta,22-tetrahydroxy-2alpha,5alpha-epidioxy-1-oxo-12,23-cycloergosta-3,24-dien-26,23-olide (7), were isolated from the leaves of Jaborosa odonelliana. Compounds 2-7 were characterized by a combination of spectroscopic methods (1D and 2D NMR, MS) and molecular modeling.     

Triterpene glycosides from Cimicifuga racemosa

Eight new triterpene glycosides named cimiracemosides A-H, respectively, and eight known triterpene glycosides were isolated from the rhizome extracts of black cohosh (Cimicifuga racemosa). The new compounds were determined by spectral data to be 21-hydroxycimigenol-3-O-alpha-L-arabinopyranoside (1), 21-hydroxycimigenol-3-O-beta-D-xylopyranoside (2), cimigenol-3-O-alpha-L-arabinopyranoside (3), 12beta-acetoxycimigenol-3-O-alpha-L-arabinopyranoside (4), 24-acetylisodahurinol-3-O-beta-D-xylopyranoside (5), 20(S),22(R), 23(S),24(R)-16beta:23;22:25-diepoxy-12beta-acetoxy-3be ta,23, 24-trihydroxy-9,19-cycloanost-7-ene-3-O-beta-D-xylopyranoside (6), 20(S),22(R),23(S),24(R)-16beta:23;22:25-diepoxy-12beta -acetoxy-3beta, 23,24-trihydroxy-9,19-cycloanost-7-en-3-O-alpha-L-arabinopyrano side (7), and 20(S),22(R),23(S), 24(R)-16beta:23;22:25-diepoxy-12beta-acetoxy-3beta,23, 24-trihydroxy-9,19-cycloanostane-3-O-beta-D-xylopyranoside (8).     

Cytotoxic withaphysalins from the leaves of Acnistus arborescens

Three withaphysalins, rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-2,24-dienolide(withaphysalin M) (1), rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-18-ethoxy-1-oxowitha-2,24-dienolide (withaphysalin F ethyl ether, withaphysalin O) (2), and rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-24-enolide (withaphysalin N) (3), were isolated from the leaves of Acnistus arborescens. The structures were deduced from 1D ((1)H NMR, (13)C NMR, DEPT-(13)C NMR) and 2D (COSY, HMQC, HMBC) NMR analysis and the relative stereochemical assignments based on 1D NOESY correlations and analysis of coupling constants. Compounds 1 and 2 displayed potent cytotoxic activity against a panel of human cancer cell lines.     

Microbial transformation of 20(S)-protopanaxatriol-type saponins by Absidia coerulea

Three 20(S)-protopanaxatriol-type saponins, ginsenoside-Rg1 (1), notoginsenoside-R1 (2), and ginsenoside-Re (3), were transformed by the fungus Absidia coerulea (AS 3.3389). Compound 1 was converted into five metabolites, ginsenoside-Rh4 (4), 3beta,2beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-beta-D-glucopyranoside (5), 20(S)-ginsenoside-Rh1 (6), 20(R)-ginsenoside-Rh1 (7), and a mixture of 25-hydroxy-20(S)-ginsenoside-Rh1 and its C-20(R) epimer (8). Compound 2 was converted into 10 metabolites, 20(S)-notoginsenoside-R2 (9), 20(R)-notoginsenoside-R2 (10), 3beta,12beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (11), 3beta,12beta-dihydroxydammar-(E)-20(22),24-diene-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (12), 3beta,12beta,20,25-tetrahydroxydammaran-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (13), and compounds 4-8. Compound 3 was metabolized to 20(S)-ginsenoside-Rg2 (14), 20(R)-ginsenoside-Rg2 (15), 3beta,12beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (16), 3beta,12beta-dihydroxydammar-(E)-20(22),24-diene-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (17), 3beta,12beta,20,25-tetrahydroxydammaran-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (18), and compounds 4-8. The structures of five new metabolites, 10-13 and 16, were established by spectroscopic methods.     

Actaeaepoxide 3-O-beta-D-xylopyranoside, a new cycloartane glycoside from the rhizomes of Actaea racemosa (Cimicifuga racemosa)

A new cycloartane glycoside (1) was obtained from a minor triterpene fraction of the rhizome extract of Actaea racemosa (synonym: Cimicifuga racemosa) along with a known compound, cimigenol 3-O-beta-D-xylopyranoside. The structure of 1 was elucidated as 20(S),22(R),23(R),24(S)-12beta-acetoxy-16beta:23,23alpha:24-diepoxy-3beta,22beta,25-trihydroxy-9,19-cyclolanost-7-ene 3-O-beta-D-xylopyranoside (actaeaepoxide 3-O-beta-D-xylopyranoside) on the basis of spectral and chemical evidence.     

穿心莲R2R3-MYB基因家族的鉴定与表达分析

R2R3-MYB是一类调控植物生长发育及次生代谢的重要转录因子.利用生物信息学手段从穿心莲全基因组中鉴定R2R3-MYB基因,分析其理化性质、染色体定位信息、基因结构和保守序列信息、系统进化信息及启动子区域的顺式作用元件.结合转录组测序技术和qRT-PCR分析其在非生物胁迫和激素诱导下的表达谱.结果 表明,穿心莲R2R...     

担子菌黄卷缘齿菌的化学成分

目的研究担子菌黄卷缘齿菌Hydnum rep andum的化学成分。方法通过硅胶、Sephadex LH-20、反相硅胶柱色谱分离化合物,运用氢谱、碳谱、二维核磁共振(1H1-HCO SY,HM QC,HM BC,NOESY)、质谱、高分辨质谱、旋光鉴定结果。结果共分离鉴定了11个化合物,分别是:sarcodon in A(Ⅰ)、scabron ine B(Ⅱ)、3β-羟基-5,α8α-过氧麦角甾-6,22-二烯-3β-醇(Ⅲ)、(22E,24R)-麦角甾-7,22-二烯-3,β5,α6β-三醇(Ⅳ)、(22E,24R)-麦角甾-7,22-二烯-3β-醇(Ⅴ)、苯甲酸(Ⅵ)、对羟基苯甲醛(Ⅶ)、对羟基苯甲酸乙酯(Ⅷ)、乙基-β-D-吡喃葡萄糖苷(Ⅸ)、硫代乙酸酐(Ⅹ)、(2S,2′R,3S,4R)-2-(2-羟基-十八碳酰胺)二十二碳烷-1,3,4-三醇(Ⅺ)。结论所有化合物都是首次在黄卷缘齿菌中分到。     

Eucosterol-type nortriterpenoids from Merwilla natalensis

The bulbs of Merwilla natalensis have yielded two known homoisoflavanones, the known spirocyclic homoisoflavanone, scillascillin, four known nortriterpenoids, and the new nortriterpenoid, (22R,23S)-17alpha,23-epoxy-22,29-dihydroxy-27-nor-lanost-8-en-3,24-dione (1), bisnortriterpenoid, (22R,23S)-17alpha,23-epoxy-3beta,22,24xi-trihydroxy-27,28-bisnor-lanost-8-ene (2), and trisnortriterpenoid, (23S)-17alpha,23-epoxy-3beta,24xi-dihydroxy-27,28,29-trisnor-lanost-8-ene (3). The structures of 1-3 were determined by spectroscopic methods.     

Tupichigenin A, a new steroidal sapogenin from Tupistra chinensis

From the underground parts of Tupistra chinensis, a novel polyhydroxylated spirostanol sapogenin, tupichigenin A [(20S, 22R)-spirost-25(27)-ene-1beta,2beta,3beta,5beta- tetraol] (1), was isolated and determined structurally on the basis of spectroscopic methods. Also isolated was the known steroidal sapogenin (20S, 22R)-spirost-25(27)-ene-1beta,2beta,3beta,4beta, 5beta, 7alpha-hexaol-6-one (2).     

轮叶棘豆的化学成分研究

目的：研究轮叶棘豆的化学成分。方法：90%乙醇冷浸提取,所得浸膏经硅胶,聚酰胺,C-18,Sephadex LH-20等多种材料进行柱色谱分离,通过波谱学方法鉴定化合物的结构。结果：分离鉴定了8个化合物,分别鉴定为azukisapogenol(1),(22E,24R)-24-甲基-5α-胆甾-7,22-二烯-3β,5α,6β-三醇(2),芹菜素(3),3′,4′-二甲氧基-槲皮素-3-O-β-D-半乳糖吡喃苷 (4),7,4′- 二甲氧基-槲皮素-3-O-α-L-鼠李糖吡喃基(1→2)-β-D-葡萄糖吡喃苷(5),(2S,3S,4R)-N-［(R)-2′-羟基二十四烷醇基］-1,3,4-三羟基-2-氨基-十八-6-烯(6),β-谷甾醇(7),胡萝卜苷(8)。结论：所有化合物均为首次从该植物中分得。     

Squarroside C, a new cycloartene bisdesmoside from Thalictrum squarrosum

Squarroside C (1), a new cycloartane 3,21-bisdesmoside, was isolated from the above-ground parts of Thalictrum squarrosum. The structure of 1 was established as 3-O-[O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyl]-21-O-be ta-D-glucopyranosyl-21(S),22(S),23(R),3beta,21alpha,22beta, 30-tetrahydroxy-21,23-epoxycycloart-24-ene by 2D NMR spectroscopy and FABMS.     

Cytotoxic constituents of the twigs and leaves of Aglaia rubiginosa

Activity-guided fractionation of a CHCl(3)-soluble extract of the twigs of Aglaia rubiginosa, using human oral epidermoid carcinoma (KB) cells as a monitor, led to the isolation of a new naturally occurring cyclopenta[b]benzofuran, 1-O-acetylrocaglaol (1), along with seven known compounds, methyl rocaglate (2), rocagloic acid (3), 1-O-acetylmethyl rocaglate (4), desyclamide, eryodictiol, 5-hydroxy-3,7,4'-trimethoxyflavone, and naringenin. A CHCl(3) extract of the leaves of A. rubiginosa yielded the new compound (3S,4R,22R)-cholest-7,24-diene-3,4,22-triol (5), as well as 11 known compounds, including 2 and 4 and cabraleone, dammarelonic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid, (20S,23E)-20,25-dihydroxy-3,4-secodammara-4(28),23-dienoic acid methyl ester, (3beta,4beta,22R)-ergosta-5,24(24')-diene-3,4,22-triol, ocotillone, shoreic acid, beta-sitosterol, and beta-sitosterol glycoside. The structures of 1 and 5 were elucidated by spectral and chemical methods. Isolates were evaluated with a human cancer cell panel, and compounds 1-4 were found to exhibit potent cytotoxic activity.     

Four cycloartane triterpenoids and six related saponins from Passiflora edulis

Four cycloartane triterpenes, cyclopassifloic acids A (1), B (2), C (3), and D (4), and six related saponins, cyclopassiflosides I (5), II (6), III (7), IV (8), V (9), and VI (10), were isolated from the leaves and stems of Passiflora edulis, and their structures were elucidated on the base of extensive NMR experiments and chemical methods. Cyclopassifloic acids A-D were assigned as 22(R), 24(S)-1alpha,3beta,22,24,31-pentahydroxy-24-methylcycloartan -28-oic acid; 24(S)-1alpha,3beta,24, 31-tetrahydroxy-24-methylcycloartan-28-oic acid; 20(S),24(S)-1alpha, 3beta,21,24,31-pentahydroxy-24-methylcycloartan-28-oic acid; and 22(R)-1alpha,3beta,22-trihydroxy-24-oxocycloartan-28-oic acid, respectively. Cyclopassiflosides I-VI, in turn, were established as the 28-O-beta-D-glucopyranosides of cyclopassifloic acids A-D. Finally, cyclopassiflosides III and V were demonstrated as the 28, 31-bis-O-beta-D-glucopyranosides of cyclopassifloic acids B and C, respectively. Also obtained in this investigation were the known compounds passiflorin (11) and passifloric acid (12).     

Structure elucidation and synthesis of dioxolanes emitted by two Triatoma species (Hemiptera: Reduviidae)

Volatiles from the metasternal glands of two species of true bugs of the Triatominae subfamily, Triatoma brasiliensis and Triatoma infestans, were analyzed by SPME-GC/MS. Two sets of new natural products were found: (4S,5S)- and (4R,5R)-2,2,4-triethyl-5-methyl-1,3-dioxolane (1) (major component) and (4S*,5S*)-2,4-diethyl-2,5-dimethyl-1,3-dioxolane (2) (trace component), (2R/S,4S,5S)- as well as (2R/S,4R,5R)-4-ethyl-5-methyl-2-(1-methylethyl)-1,3-dioxolane (3) (minor component), (2R/S,4S*,5S*)-4-ethyl-5-methyl-2-(1-methylpropyl)-1,3-dioxolane (4) (trace component), and (2R/S,4S*,5S*)-4-ethyl-5-methyl-2-(2-methylpropyl)-1,3-dioxolane (5) (trace component). Syntheses of optically active 1 and 3 were carried out by reacting pure enantiomers of 2,3-pentanediol with 3-pentanone or 2-methylpropanal. The preparation of pure stereoisomers of 2,3-pentanediol involved a novel key step for the synthesis of secondary alcohols: the reduction of a carboxylic ester by means of DIBAH and in situ alkylation of the intermediate by Grignard reaction at low temperature. Starting from the pure enantiomers of methyl lactate, all four stereoisomers of 2,3-pentanediol were synthesized and transformed to the corresponding isomers of 1 and 2. Relative configurations of the natural products and enantiomeric compositions of naturally occurring 1 and 2 were determined by comparison of their mass spectra and gas chromatographic retention times (co-injection) with those of authentic reference samples.     

桑椹醇提物的化学成分研究

目的研究桑椹Mori Fructus醇提物的化学成分。方法采用硅胶、Sephadex LH-20和ODS柱色谱法及半制备型高效液相色谱进行分离纯化,通过其理化性质和波谱数据对化合物结构进行鉴定。结果从桑椹醇提物中分离得到12个化合物,分别鉴定为桑脂素苷(1)、(7R,8S)-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(2)、2-苯乙基-β-D-吡喃葡萄糖苷(3)、1′-O-苯乙基-β-D-呋喃芹菜糖基-(1→2)-β-D-吡喃葡萄糖苷(4)、苯甲醇-O-β-D-吡喃葡萄糖苷(5)、过氧麦角甾醇(6)、(24R)-6β-hydroxy-24-ethyl-cholest-4-en-3-one(7)、(22E)-5α,8α-epidioxy-24-methyl-cholesta-6,9(11),22-trien-3β-ol(8)、trans-(S)-(+)-脱落酸(9)、cis-(S)-(+)-脱落酸(10)、(S)-(+)-1-甲基-脱落-6-酸(11)、菜豆酸(12)。结论化合物1为未见文献报道的新化合物,化合物2、7~12为首次从该植物中分离得到。     

Preparation of moreliane-derived volatile sesquiterpenes

A series of six volatile sesquiterpenes (9-13 and 15) was prepared by thioketalization of (4R,5S,9S,10S,11S)-morel-2-en-1,7-dione (2) and of (4R,5S,7R,9R,11R)-moreli-2,10-dien-7-ol-1-one (3), followed by Raney-nickel desulfurization. The structures of the new substances were determined by 1D and 2D NMR including COSY, NOESY, HSQC, and HMBC experiments. The geometry of (3S,4R,5R,9S,10R,11S)-morelian-7-one (11), which exhibited an intense woody odor, was calculated by density functional theory at the B3LYP/6-31G level.     

人参茎叶总皂苷的人肠内细菌生物转化

目的:研究人参茎叶总皂苷的人肠内细菌生物转化。方法:采用液相色谱-电喷雾离子源-四极杆-飞行时间质谱法(LC-ESI-Q-TOF-MS)负离子监测模式,对人参茎叶总皂苷样品和人肠内细菌转化的人参茎叶总皂苷样品进行定性分析,将采集的原始数据导入分析软件进行碎片和相对分子质量匹配,根据高分辨质谱信息推导可能的裂解碎片;部分化合物通过与对照品比对进行解析,比较2个样品中人参达玛烷三萜化合物的差别。结果:在人参茎叶总皂苷样品中共鉴定出83个化合物,在人肠内细菌转化人参茎叶总皂苷的样品中共鉴定出67个化合物,包括区别性化合物20(S)-25-OH-原人参三醇[20(S)-25-OH-PPT]、20(R)-25-OH-PPT、人参皂苷O(G-O)、绞股蓝皂苷Ⅸ、绞股蓝皂苷ⅩⅦ、25-OH-G-Rh₂、20(22)E-G-Rg₉、G-Rs₃、20(R)-G-Rs₃、G-Mc、G-Y、G-Mx、20(S)-25-OH-原人参二醇[20(S)-25-OH-PPD]、G-CK和G-CK异构体。结论:人参茎叶总皂苷经人肠内细菌生物转化后产生了低极性的达玛烷型人参三萜类化合物;提示人参茎叶总皂苷经人肠内细菌生物转化后更利于其吸收进入系统循环。     

Antifungal 3-butylisocoumarins from Asteraceae-Anthemideae

Seven new naturally occurring 3-butylisocoumarins were isolated and identified from lipophilic extracts of aerial as well as underground organs: corfin (17) and 3'-hydroxycorfin (18) from the roots of Chamaemelum mixtum and (-)-(R)-2'-methoxydihydroartemidin (5), (+)-(S,R)-epoxyartemidin (6a), dracumerin (12), (+)-(R)-(E)-3'-hydroxyartemidin (13), and capillarin isovalerate (20) from various organs of Artemisia dracunculus (tarragon). Furthermore, six known derivatives, artemidiol (7), (E/Z)-artemidin (11), capillarin (19), artemidinol (21), 8-hydroxyartemidin (22), and 8-hydroxycapillarin (23), were obtained. The antifungal activities of all naturally occurring derivatives were determined in a germ-tube inhibition test against a susceptible strain of rice blast fungus Pyricularia grisea. The 3-butyl side-chain is a prerequisite for high activity. Eleven structurally related synthetic derivatives were additionally tested to explore the influence of structural characteristics on activity. Benlate, blasticidin S, kresoxim-methyl, griseofulvin, and the carrot phytoalexin 6-methoxymellein all served as positive controls.     

Absolute configuration of 7,8-seco-7,8-oxacassane diterpenoids from Acacia schaffneri

Chemical investigations of Acacia schaffneri led to the isolation of the new diterpenoid (5S,7R,8R,9R,10S)-(-)-7,8-seco-7,8-oxacassa-13,15-diene-7,17-diol (1), together with the known (5S,7R,8R,9R,10S)-(-)-7,8-seco-7,8-oxacassa-13,15-dien-7-ol-17-al (2) and (5S,7R,8R,9R,10S)-(-)-7,8-seco-7,8-oxacassa-13,15-dien-7-ol (3). Compounds 2 and 3 were analyzed by single-crystal X-ray diffraction, while the structure of 1 was determined by 1D and 2D NMR experiments and by chemical correlation with 2. Oxidation of 3 afforded conformationally restricted (5S,8R,9R,10S)-(-)-8-hydroxy-7,8-seco-cassa-13,15-dien-7-oic acid ε-lactone (4), which was studied by vibrational circular dichroism spectroscopy. Comparison of the experimental VCD spectrum of 4 with the DFT//B3PW91/DGDZVP2 calculated spectrum assigned for the first time the absolute configuration of these seco-oxacassane diterpenes.